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31.
In-vitro maturation of human germinal vesicle stage oocytes: role of cumulus cells and epidermal growth factor in the culture medium 总被引:21,自引:6,他引:21
Goud PT; Goud AP; Qian C; Laverge H; Van der Elst J; De Sutter P; Dhont M 《Human reproduction (Oxford, England)》1998,13(6):1638-1644
In-vitro maturation (IVM) of oocytes is a promising technique to reduce the
costs and avert the side-effects of gonadotrophin stimulation for in-vitro
fertilization (IVF). The pregnancy rates from oocytes matured in vitro are
much lower than those of in-vivo stimulation cycles indicating that
optimization of IVM remains a challenge. Therefore, we investigated the
effect of supplementation of the medium with gonadotrophins, oestradiol and
epidermal growth factor (EGF) and the effect of retaining or removing the
cumulus cells on nuclear and cytoplasmic maturation of immature oocytes.
Human germinal vesicle (GV) oocytes obtained after gonadotrophin
stimulation for intracytoplasmic sperm injection (ICSI) were cultured in a
complex defined medium either supplemented with gonadotrophins, oestradiol
and physiological concentrations of EGF (2 ng/ml) or gonadotrophins and
oestradiol alone. The cumulus cells were either removed or kept intact. In
GV stage oocytes cultured without cumulus (group I) significantly more
oocytes reached the metaphase II (MII) stage at 30 h in media supplemented
with EGF (64.3 versus 33.9%, P < 0.003). For oocytes cultured with
intact cumulus (group II), more oocytes reached MII at 30 h than in group
I, but there was no difference in medium with or without EGF
supplementation (81.8 and 79.8% respectively). Cytoplasmic maturation of
MII oocytes was judged from their capability to activate and fertilize
after ICSI. In group I, the rates of activation and normal fertilization
were similar. However, in group II, significantly more oocytes underwent
normal fertilization in the EGF-supplemented than the unsupplemented group
(71.7 versus 45.6%, P < 0.05). The cleavage rates of the fertilized
oocytes were similar in the sibling oocyte subgroups cultured with or
without EGF supplementation, but the overall cleavage rates were higher in
cumulus-intact compared to cumulus-denuded oocytes (88.9 versus 47.8%, P
< 0.001). Thus, supplementation of the maturation medium with EGF and
maintenance of the cumulus during culture improve the nuclear and
cytoplasmic maturation of human oocytes in vitro.
相似文献
32.
N. Ohara Dr. K. Hayashi K. Miyamoto K. Takahashi Y. Ohtsuki T. Akagi 《Archives of virology》1995,140(7):1291-1295
Summary We observed expression of envelope gp46 protein on an HTLV-II-producing T-cell line (Mo) cells by an immunoelectron microscopical method using a monoclonal antibody against HTLV-II gp46. gp46 reactivity was observed on virus-like particles, extracellular vesicles, cell membrane, and partially in nuclear membrane and endoplasmic reticulum. 相似文献
33.
Ontogeny of macrophage-mediated protection against Listeria monocytogenes. 总被引:1,自引:3,他引:1
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We investigated the ontogenic development of macrophage functions which are important in the expression of host defense against infection by Listeria monocytogenes. Macrophage functions, including accumulation in response to local stimuli, chemotaxis in vitro, and intracellular killing, as well as number of macrophages, were examined by using mice 1, 2, 3, 4, and 8 weeks old. The number of peritoneal macrophages was extremely low in younger mice even when their body weights were taken into consideration. Macrophage accumulation in response to infectious stimulus with viable listeria was poor in younger mice and showed an age-dependent development. In younger groups, chemotaxis in vitro was as immature as chemotaxis in vivo. In 1- and 2-week-old mice, macrophages did not show any intracellular killing activity against L. monocytogenes, but killing was observed in mice over 3 weeks of age. These functions developed in an age-dependent manner and reached the 8-week-old adult level after the mice were 4 weeks of age. In adult mice, these macrophage functions were shown to be enhanced after immunization with viable listeria; however, such an immunization-induced enhancement was very poor in the younger groups of mice. Protection judged by mortality and in vivo bacterial growth was weaker in the younger groups against both primary and secondary challenges. In vivo protection against L. monocytogenes seemed to develop in the same age-dependent manner as the development of macrophage functions. These results indicate that age-dependent immaturity of macrophage functions mainly comprises the age-dependent immaturity of protection against L. monocytogenes. 相似文献
34.
N Koyama K Ohara H Yokota T Kurome M Katayama F Hino I Kato T Akai 《Journal of immunological methods》1991,139(1):17-23
A highly sensitive, simple and reliable one-step sandwich enzyme immunoassay (EIA) for the gamma-carboxylated form of osteocalcin (Gla-OC) has been developed using a monoclonal antibody. The minimum amount of Gla-OC detected by this EIA was approximately 0.2 ng/ml when a 10 microliter aliquot of the sample was used. The serum Gla-OC level in 30 healthy subjects was 3.6 +/- 2.19 ng/ml (mean +/- SD). A significant increase was seen in patients with chronic renal failure (20.3 +/- 4.60 ng/ml), atherosclerosis (8.3 +/- 4.94 ng/ml) and osteoporosis (10.1 +/- 4.60 ng/ml). The correlation between the values obtained by the sandwich EIA and competitive RIA methods was given by the linear regression equation, y = 2.896 + 0.759 chi, for which the correlation coefficient (r) was 0.815 (n = 58). This newly developed Gla-OC specific EIA may be useful for the diagnosis of metabolic bone disease and ectopic calcification. 相似文献
35.
Hoshi T Sasano H Kato K Ohara S Shimosegawa T Toyota T Nagura H 《Human pathology》1999,30(12):1412-1417
Helicobacter pylori (HP) is believed to be involved in the transition from normal gastric mucosa to atrophic gastritis and intestinal metaplasia. Infection with the organism is one of the risk factors for development of intestinal-type gastric adenocarcinoma, possibly through altered cell turnover. Medical eradication of HP is widely performed for the treatment of peptic ulcers and other upper gastrointestinal disorders. Eradication of HP may affect altered cell turnover of the gastric mucosa caused by the infection, but there are few reports comparing sterilized mucosa with HP-infected and non-infected mucosa. In this study, we examined cell damage using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL), in situ nick translation (ISNT), and cell proliferation by Ki 67 immunohistochemistry staining in gastric mucosa before and after HP eradication and in non-infected gastric mucosa. We then compared these findings using endoscopic gastric biopsy specimens. Labeling indices of TUNEL (2.46 +/- 1.22), ISNT (1.13 +/- 0.42), and Ki67 (21.8 +/- 6.14) in tissue from which HP had been eradicated were significantly lower than those of HP-infected mucosa (6.36 +/- 2.26, 4.00 +/- 1.62, 45.8 +/- 5.35, for TUNEL, ISNT, and Ki67, respectively). There were no significant differences between formerly infected and non-infected mucosa (TUNEL: 2.26 +/- 0.69, ISNT: 1.29 +/- 0.63, Ki67: 23.5 +/- 8.20). These results indicate that medical HP eradication results in decreased cell proliferation and damage, restoring the condition seen in non-infected mucosa. Thus, HP eradication may be effective, not only in the treatment of gastric ulcers or gastric symptoms, but also in the prevention of gastric carcinoma. 相似文献
36.
William R. Leonard PT Katzmarzyk Anthony G. Comuzzie Michael H. Crawford Rem I. Sukernik 《American journal of human biology》1994,6(3):339-350
This study examines physical growth and nutritional status in a sample of 478 (247 males; 231 females) Evenki herders of Central Siberia. The Evenki display slow growth in stature and body weight, particularly during late childhood and adolescence. Adult males fall below the U.S. 5th percentiles for both stature and body weight. Adult females are below the 5th percentile for stature and approximate the 15th percentile for weight. Despite their diminutive size, the Evenki appear to have adequate energy reserves, as indicated by their skinfold measurements, which range between the U.S. 15th and 50th percentiles. Among adults, women are relatively heavier and fatter than men and tend to increase in weight and fatness with age. Poor growth in the Evenki does not appear to be directly attributable to limited food availability. Rather, it is hypothesized that elevated metabolic requirements, associated with adaptation to a high latitude ecosystem, are responsible for limiting the amount of energy that is allocated to growth. Relatively high levels of adiposity in adult females appear to be the product of changes in activity patterns and fertility levels that resulted after the collectivization of the Evenki. © 1994 Wiley-Liss, Inc. 相似文献
37.
N. Kariya K. Hayashi H. Hoshino Y. Tanaka T. R. Koirala N. Ohara K. Miyamoto T. Akagi 《Archives of virology》1996,141(3-4):471-480
Summary Rabbit immune sera raised against synthetic peptides of the HTLV-II envelope gp46 region were examined for HTLV-II neutralization ability by HTLV-vesicular stomatitis virus (VSV) pseudotype assay and syncytium inhibition assay. HTLV-II neutralization activity was detected in the sera against HTLV-II Env gp46, 80–103 but not in those to HTLV-II Env gp46, 171–196. Three rabbits immunized with the synthetic peptide of HTLV-II Env gp46, 80–103 and three non-immunized rabbits were challenged with intravenous inoculation of an HTLV-II-producing human cell line (MOT, 1×107 cells). The non-immunized rabbits showed seroconversion for HTLV-II after 2 weeks and maintained persistent infection but the immunized rabbits were protected from HTLV-II infection. Nested or repeated polymerase chain reaction revealed the presence of HTLV-II provirus sequences in the non-immunized rabbits but not in the immunized rabbits. These results suggest that peptide vaccination with a synthetic peptide corresponding to the HTLV-II neutralization region is useful for preventing HTLV-II infection. 相似文献
38.
Kinetic profiles of sequential gene expressions for chemokines in mice with contact hypersensitivity
Using cDNA microarray technology, the expression of chemokine genes in the elicitation site of 2,4,6-trinitrochlorobenzene-induced contact hypersensitivity (CHS) was examined in mice. Of the 33 genes analyzed, levels of 11 gene expressions changed, and these can be assigned to four groups based on their kinetic patterns; (1) LARC/CCL20 whose mRNA level increased rapidly at 3 h post-challenge and then gradually decreased, (2) JE/CCL2, MARC/CCL7, MIP-1gamma/CCL9, monocyte chemoattractant protein (MCP)-5/CCL12, ELC/CCL19 and BRAK/CXCL14 whose mRNA levels increased with time and reached the maximum at 6-9 h post-challenge, (3) LIX/CXCL5, Mig/CXCL9 and IP-10/CXCL10 whose mRNA levels increased gradually at least up to 12 h post challenge, and (4) SLC/CCL21 whose mRNA level decreased gradually with time after challenge. The findings suggest that sequential expression of chemokine genes is essential for orientating non-specific skin response to hapten-specific CHS response through the recruitment of inflammatory cells such as neutrophils, monocytes/macrophages and T-cells from the circulation into the tissue site. 相似文献
39.
Kirkpatrick SE; Pitlick PT; Naliboff J; Friedman WF 《The American journal of physiology》1976,231(2):495-500
40.
Polymerization of 1.3-dimethylcyclopentadiene was carried out with FRIEDEL -CRAFTS and ZIEGLER -type catalysts. All polymers obtained were soluble. The polymers had 45 to 55% 1.4-structure and 55?45% 3.4-structure. The polymerization appears to go through a tertiary carbonium ion, in contrast to that of monosubstituted cyclopentadienes. In copolymerization of 1.3-dimethylcyclopentadiene (M1) with cyclopentadiene (M2), the former showed higher reactivity: r1 = 6.85 ± 1.10, r2 = 0.30 ± 0.10, at ?78°C. Comparison of the structures of polymers obtained by cationic polymerization of substituted cyclopentadienes revealed a general mechanism which explains the mode of the monomer addition. 相似文献